The hip joint is know as a ball and socket joint, allowing backward, forward, sideways and rotating movements. This joint is formed by the top of the femur (thighbone) and the socket of the pelvic bone. At the top of the femur is a ball which fits snugly into the socket. A normal, healthy joint will move freely without pain. In addition to the bones, the hip joint consists of the following:
- Cartilage – at the joint, the bones are covered with cartilage (a connective tissue), made up of cell and fibers and is wear-resistant. Cartilage helps reduce the friction of movement.
- Synovial membrane – a tissue lining the joint which acts and seals it into the joint capsule. The synovial membrane secretes synovial fluid (a clear, sticky fluid) around the joint to lubricate it.
- Ligaments - tough, elastic bands of connective tissue which surround the joint to give support and limit the joint’s movement.
- Tendons – another type of tough connective tissue on each side of the joint attached to muscles that control movement of the joint.